Basic physical types

7.3.1 Says that the 8 types mass, length, time, angle, temperature, luminous_intensity, electrical_current and amount_of_substance are "basic physical types" and that: "Other types and units (like speed, angular_rate, pressure, and illuminance, among others) are defined in the domain model." However, the basic physical types are also defined in the domain model and in standard.osc, so are they supposed to be predefined in the language or are they part of the domain model and thus need to be explicitly defined (e.g. by importing osc.standard) to have them available?